1. Field of the Invention
The present invention relates to a steering shaft support structure for steering the front wheels of a vehicle for uneven ground operation.
2. Description of Background Art
A steering shaft support structure is known that is provided with a steering bracket. See for example, Japanese Examined Patent Publication No. HEI 6-92237 (Page 3, FIG. 1).
FIG. 1 of Japanese Examined Patent Publication No. HEI 6-92237 will be described with reference to FIG. 6 of the drawings attached to the present specification. It is to be noted that reference numerals in FIG. 6 have been reassigned and are not the same reference numerals as set forth in Japanese Examined Patent Publication No. HEI 6-92237.
FIG. 6 is a side view of a conventional embodiment showing a conventional steering shaft support structure. A saddle-type vehicle is illustrated wherein a steering bracket 102 is mounted on the front portion of the body frame 101, the front face of the steering bracket 102 is provided with a shaft strut portion 103, and the steering shaft 104 is supported at the shaft strut portion 103.
A steering support structure is also known as shown in FIG. 7.
FIG. 7 is a side view of a conventional embodiment showing a conventional steering shaft support structure, wherein the mounting of front and rear holders 113 and 114 on a body frame 116 is effected by inserting a steering shaft 111 through a bushing 112, sandwiching the bushing 112 between the front and rear holders 113 and 114, and screwing bolts 118 and 118 into nuts 117 and 117 provided on the body frame 116. Here, a bar handle 121 is mounted on the upper portion of the steering shaft 111 via hand holders 122 and 122.
The saddle-type vehicle shown in FIG. 6 aims at an uneven ground operation. Since the vehicle operates on uneven ground, such as a craggy place or a sandy place, it is required to have mobility. Accordingly, a body light in weight and high is rigidity is desired.
If the steering bracket 102 is replaced with a part of the body frame 101, the number of components is reduced so that a reduction in weight is achieved. If the rigidity of the body can be enhanced by, e.g., altering the configuration of a part of the body frame 101 without adding an extra component to the body frame 101, the weight increase can be suppressed.
Since the steering shaft 111 is supported also at each of the rear holder 114 and body frame 116 of the body in FIG. 7, the integration of these components should be considered.